diff --git a/src/hyperbolic.jl b/src/hyperbolic.jl
index f2ba182..804039e 100644
--- a/src/hyperbolic.jl
+++ b/src/hyperbolic.jl
@@ -11,7 +11,7 @@ The pair `(c, x_new)` where
 - `c` is unchanged
 - `x_new` is the interval hull of the set ``{x ∈ b : sinh(x) ∈ a}``
 """
-function sinh_rev(y::Interval, x::Interval)
+function sinh_rev(y::Interval, x::Interval = entireinterval(y)
     x = x ⊓ asinh(y)
 
     return y, x
@@ -30,7 +30,7 @@ The pair `(c, x_new)` where
 - `c` is unchanged
 - `x_new` is the interval hull of the set ``{x ∈ b : cosh(x) ∈ a}``
 """
-function cosh_rev(y::Interval,x::Interval)
+function cosh_rev(y::Interval, x::Interval = entireinterval(y))
     y_new = y ⊓ interval(1.,∞)
     x = (x ⊓ acosh(y)) ⊔ (x ⊓ -acosh(y))
 
@@ -50,7 +50,7 @@ The pair `(c, x_new)` where
 - `c` is unchanged
 - `x_new` is the interval hull of the set ``{x ∈ b : tanh(x) ∈ a}``
 """
-function tanh_rev(y::Interval,x::Interval)
+function tanh_rev(y::Interval, x::Interval = entireinterval(y))
     y_new = y ⊓ interval(-1.,1.)
     x = x ⊓ atanh(y)
 
diff --git a/src/trig.jl b/src/trig.jl
index 23c7616..90d21a9 100644
--- a/src/trig.jl
+++ b/src/trig.jl
@@ -139,7 +139,7 @@ function tan_main(X::IntervalBox)
 
 end
 
-tan!(X::IntervalBox) = periodise(tan_main, Interval{Float64}(π))(X)
+tan!(X::IntervalBox) = periodise(tan_main, interval(π))(X)
 
 """
     tan_rev(c::Interval[, x::Interval])
@@ -154,7 +154,7 @@ The pair `(c, x_new)` where
 - `c` is unchanged
 - `x_new` is the interval hull of the set ``{x ∈ b : tan(x) ∈ a}``
 """
-function tan_rev(y::Interval, x::Interval)
+function tan_rev(y::Interval, x::Interval = entireinterval(y))
 
     X = IntervalBox(x, y)